Amelioration of diabetes-induced cavernosal fibrosis by antioxidant and anti-transforming growth factor-ß1 therapies in inducible nitric oxide synthase-deficient mice.

OBJECTIVE: • To investigate whether sustained long-term separate treatments of diabetic inducible nitric oxide synthase knockout (iNOSKo) mice with allopurinol, an antioxidant inhibiting xanthine oxidoreductase, decorin, a transforming growth factor-ß1 (TGFß1) -binding antagonist, and molsidomine, a long-life nitric oxide donor, prevent the processes of diabetes-induced cavernosal fibrosis. MATERIALS AND METHODS: • Eight week old male iNOS knock out (iNOSKo) mice were made diabetic by injecting 150 mg/kg B.W Streptozotocin (1P) with were either left untreated or treated with the oral antioxidant allopurinol (40 mg/kg/day), or decoin (50 mg, 1P, twice), as an anti-TGFß1 agent (n = 8/group). • Glycemia and oxidative stress markers were determined in blood and urine. • Paraffin-embedded tissue sections from the penile shaft were subjected to Masson trichrome staining for the smooth muscle (smc)/collagen ratio, and imunostaining for smc content, profibrotic factors, oxidative stress, cell replication and cell death markers followed by quantitative image analysis. RESULTS: • Eight-week treatment with either allopurinol or decorin counteracted the decrease in smooth muscle cells and the increase in apoptosis and local oxidative stress within the corpora tissue. • Decorin but not allopurinol increased the smooth muscle cell/collagen ratio, whereas allopurinol but not decorin inhibited systemic oxidative stress. • Molsidomine was effective in reducing both local and systemic oxidative stress, but did not prevent corporal fibrosis. CONCLUSION: • Both allopurinol and decorin appear as promising approaches either as a single or a combined pharmacological modality for protecting the diabetic corpora from undergoing apoptosis and fibrosis although their functional effects still need to be defined.

A Case of Acute Myeloid Leukemia-Associated Necrotizing Sweet Syndrome.

Sweet syndrome (SS), or acute febrile neutrophilic dermatosis, is a rare painful skin condition that is characterized by hyperpyrexia, peripheral blood and skin neutrophilia, and edematous skin lesions. Necrotizing SS (NSS) is a severe and locally aggressive condition that histopathologically resembles a necrotizing soft tissue infection. As opposed to necrotizing soft tissue infections, NSS responds to systemic steroids. SS is divided into three subtypes: classical SS, malignancy-associated SS, and drug-induced SS. Within the malignancy-associated SS subtype, both solid tumor and hematologic malignancies have been precursors to developing SS. Here, we present a case of acute myeloid leukemia-associated NSS.

The genetic inactivation of inducible nitric oxide synthase (iNOS) intensifies fibrosis and oxidative stress in the penile corpora cavernosa in type 1 diabetes.

INTRODUCTION: Endogenously elicited inducible nitric oxide synthase (iNOS) induction counteracts fibrosis and oxidative stress in penile tissues in rat models of Peyronie's disease and erectile dysfunction. AIM: The current study aimed to determine whether the genetic blockade of iNOS expression in the iNOS knock out (iNOS KO) mouse intensifies fibrosis and oxidative stress in the penile corpora cavernosa, and this is exacerbated by streptozotocin (STZ)-induced diabetes and counteracted by insulin. MAIN OUTCOMES MEASURES: Quantitative assessment of histological and biochemical markers in mouse corporal tissue. METHODS: Male iNOS KO and wild type (WT) mice were left untreated or injected with STZ, with or without insulin treatment. At 8 weeks, glycemia, glucosuria, and proteinuria were determined, and corporal tissue sections were obtained and subjected to Masson trichrome staining for smooth muscle (SM)/collagen ratio, and immunostaining for α-smooth muscle actin (ASMA) for, SM content, proliferating cell nuclear antigen (PCNA) for cell replication, TGFß1 as profibrotic factor, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay for apoptosis, and xanthine oxidoreductase (XOR) for oxidative stress. Collagen was estimated by the hydroxyproline reaction. RESULTS: The corporal SM/collagen ratio and SM content were reduced, and collagen content increased in iNOS KO mice as compared with WT mice, but apoptosis was decreased and cell replication increased, whereas TGFß1 and XOR did not vary. Severe hyperglycemia caused in the WT a reduction of the corporal SM/collagen ratio and SM content and an increase in apoptosis without changes in PCNA, TGFß1, or XOR. In the iNOS KO mouse the hyperglycemia-induced alterations were exacerbated, with additional increases in oxidative stress and TGFß1. Insulin normalized glycemia and partially protected the SM in both the WT and the iNOS KO mice. CONCLUSIONS: The antifibrotic, antioxidative, and SM-protective roles of iNOS in the penile corpora cavernosa were confirmed in the iNOS KO/STZ mouse model. These findings support the importance of endogenously-elicited iNOS induction in protecting the penile corpora cavernosa from the pro-fibrotic effects of hyperglycemia.

The pivotal role of CCN2 in mammalian palatogenesis.

Mammalian palatogenesis is a complex process involving a temporally and spatially regulated myriad of factors. Together these factors control the 3 vital processes of proliferation, elevation and fusion of the developing palate. In this study, we show for the first time the unequivocally vital role of CCN2 in development of the mammalian palate. We utilized CCN2 knockout (KO) mice and cranial neural crest derived mesenchymal cells from these CCN2 KO mice to investigate the 3 processes crucial to normal palatogenesis. Similar to previously published reports, the absence of CCN2 inhibits proliferation of cells in the palate specifically at the G1/S transition. Absence of CCN2 also inhibited palatal shelf elevation from the vertical to horizontal position. CCN2 KO mesenchymal cells demonstrated deficiencies in adhesion and spreading owing to an inability to activate Rac1 and RhoA. On the contrary, CCN2 KO mesenchymal cells exhibited increased rates of migration compared to WT cells. The addition of exogenous CCN2 to KO mesenchymal cells restored their ability to spread normally on fibronectin. Finally, utilizing an organ culture model we show that the palatal shelves of the CCN2 KO mice demonstrate an inability to fuse when apposed. Together, these data signify that CCN2 plays an indispensible role in normal development of the mammalian palate and warrants additional studies to determine the precise mechanism(s) responsible for these effects.

UNC93B1 mediates differential trafficking of endosomal TLRs.

UNC93B1, a multipass transmembrane protein required for TLR3, TLR7, TLR9, TLR11, TLR12, and TLR13 function, controls trafficking of TLRs from the endoplasmic reticulum (ER) to endolysosomes. The mechanisms by which UNC93B1 mediates these regulatory effects remain unclear. Here, we demonstrate that UNC93B1 enters the secretory pathway and directly controls the packaging of TLRs into COPII vesicles that bud from the ER. Unlike other COPII loading factors, UNC93B1 remains associated with the TLRs through post-Golgi sorting steps. Unexpectedly, these steps are different among endosomal TLRs. TLR9 requires UNC93B1-mediated recruitment of adaptor protein complex 2 (AP-2) for delivery to endolysosomes while TLR7, TLR11, TLR12, and TLR13 utilize alternative trafficking pathways. Thus, our study describes a mechanism for differential sorting of endosomal TLRs by UNC93B1, which may explain the distinct roles played by these receptors in certain autoimmune diseases.DOI:http://dx.doi.org/10.7554/eLife.00291.001.